Not T&T by me, but high ratings for Alton Brown cocoa version
Here's some quick math (probably wrong...I've been up since 1:30 A.M):
Alton's recipe fills an 8x8 pan = 64 sq in.
3x of his = 192 sq in
1/2 sheet cookie (jellyroll, ~17'x12") = 204 sq in.
So Alton's scaled up by 3x will fill a half sheet.
You can get 54 ~2" squares out of a half-sheet.
Two half sheets would get you 100 2" brownies.
Here are his ingredients and below that I have indicated 1 batch, 3x batch (to fill a half sheet) and 6x batch (how much you would need to prepare two half-sheets)
Ingredients 1x 3x 6x
4 large eggs
4 eggs 12 eggs (1 doz) 24 eggs (2 doz)
1 cup sugar, sifted
1C 3C 6C
etc...
1 cup brown sugar, sifted
1C 3C 6C
8 ounces melted butter
8oz 24oz (1.5 lb) 48 oz (3 lb)
11/4 cups cocoa, sifted
1.25 C 3.75C 7.5C
2 teaspoons vanilla extract
2tsp 6 tsp (2 Tbl) 12 tsp (4 Tbl = 1/4C)
1/2 cup flour, sifted
0.5C 1.5C 3C
1/2 teaspoon kosher salt
0.5tsp 1.5tsp 3tsp (1 Tbl)
http://www.foodnetwork.com/recipes/alton-brown/cocoa-brownies-recipe/index.html